This invention relates generally to valves, and more particularly to a valve having a spool-type valve member driven by a linear, spring biased actuator including a cap which releasably latches the valve in its open position.
There is a need for a valve which, while attached to a surgical instrument such as an irrigation/aspiration probe, can be operated with one hand. Ergonomically, it is desirable for a valve to be mounted at right angles to a probe, and to attach to a standard medical luer taper.
It is also desirable to avoid placing a return spring within the fluid flowpath, and to provide a design that permits in-line vertical assembly of components without gluing or welding, to facilitate high volume, low cost production.
A valve satisfying the above requirements is disclosed in U.S. Pat. No. 5,064,168, which is incorporated herein by reference. In that valve, a spool-shaped head is moved from a closed position to an open position by depressing a cap against the force of a spring within the cap. When the cap is released, the valve closes automatically. In some applications, however, it would be desirable to be able to lock or latch the valve in an open position. There are a number of prior valves, particularly faucet valves, having a latch-open feature. Prior approaches tend to be too bulky, complicated, or costly to be suitable for use in a small, inexpensive medical infusion valve.